RESUMEN
A female adnexal tumor of probable Wolffian origin (FATPWO) is a rare neoplasm believed to originate from Wolffian remnants because the tumors are located in areas where such remnants are abundant. Because FATPWO is so rare that tumor biological behavior is not well defined, especially in cases of ovarian tumors, the collection and investigation of all relevant data, including this case report, are thus crucial to identify the best possible treatment for this type of tumor. We report a 14-year-old girl presented with a huge ovarian tumor that is reminiscent of dysgerminoma on CT scan. Left salpingo-oophorectomy was perfomed. Because the pathologic report on frozen section was malignant neoplasm, additional surgical staging was performed. A ovarian tumor of probable Wolffian origin was diagnosed by the pathologist, finally. No adjuvant therapy was given and there was no clinical evidence of recurrence during the 19 months of follow-up.